In the construction of belted tires, the belt or breaker components are generally stored in stock rolls between adjacent convolutions of a liner. Such components may be precut and can seldom be stored uniformly centered. Yet such components must be applied to the drum carefully centered to attain the required precision in radial or belted tire construction. Many tire building systems employ complex optical or guidelight systems to obtain the desired centering.
A simplified mechanical guiding system is of course preferable to obtain centering but the nature of tire components such as belts or breakers makes them difficult to handle mechanically and subject to distortion which should be avoided.
In belt servicers, it is common practice to permit the belt to hang freely in a loop or festoon, the extent of which is approximately one revolution of the belt building drum. This permits one revolution of the belt to be applied quickly with the loop or festoon simply being taken up. However, when the belt is provided with metallic wire reinforcement, it is sufficiently heavy that in the loop or festoon it may elongate slightly causing distortion even to the extent of changing the angle of the wire or the width of the belt. Accordingly, wire or other heavily reinforced belts should not be looped or festooned free of the liner but should be supported upon leaving the liner so as to avoid the possiblity of elongation.
Moreover, many prior art servicers are extremely complex and occupy an inordinate amount of space. Such servicers cannot readily be relocated from one location to another in a tire plant.
Examples of prior art servicers may be seen in Enders et al U.S. Pat. No. 3,795,563. Other examples of well known and relatively complex prior art servicers may be seen in the U.S. patents to Mallory No. 2,658,691, Mallory et al Nos. 3,216,879, and 3,230,132, and Cantarutti No. 3,278,360.